Not to mention "www", which when pronounced is actually three times longer than its expansion.

sheept 2 hours ago | parent | next [-]

For a native speaker in casual speech, it'll only be at most a bit slower than its expansion because English is stress-timed

layer8 2 hours ago | parent | prev [-]

You could shorten it to “sextuple u”.

	▲	b112 an hour ago \| parent [-]
		Great minds think alike, but my concern was that sextuple-u sounds like you're about to tackle someone and do something.